The objective of the proposal is to stimulate additional gerontological research at the University of Nebraska by conducting a collaborative project which will 1) allow several investigators currently involved in aging research to enhance and expand their programs and 2) allow their investigators currently not involved in gerontological research but well established in other fields -- to conduct pilot studies in aging. This study should provide the participating scientists with sufficient data and familiarity with the field of gerontology to subsequently develop independent gerontological research programs. A colony of aging C57BL/6 mice will be maintained from which the participating investigators will do pilot and in some cases collaborative studies in their areas of interest. The effects of age on interferon production, the microenvironment of hematopoietic stem cells, intestinal cell kinetics, hepatic drug metabolism, purine metabolism, asparagine synthesis, sexual behavior and reproductive physiology will be studied. In addition, the effect of a growth-hormone-like factor produced by plerocercoid larvae of the tapeworm Spirometra mansonoides on age-related decline in immune function, drug metabolism and life span of the animals will be determined. Interest in aging research will be further stimulated by 1) bringing together the participating investigators from the various campuses for presentation and discussion of aging studies in a "Journal Club" setting 2) having authorities on gerontology visit the University and 3) having the participating investigators attend workshops and symposia on aging for specialized off-campus training and enrichment.